As communication technologies have developed, electronic devices, for example, a portable terminal such as a smart phone, a tablet Personal Computer (PC), a smart camera, a digital camera, and the like, have become widely utilized. A portable terminal are utilized in a significantly wide field since the portable terminal is convenient to use and easy to carry.
Recently, a camera that provides a performance of high-definition and high-resolution has been contained in a portable terminal and thus, a user's desire for readily photographing a picture and/or a video has been increased. Accordingly, an auto-focusing system has been provided that automatically focuses on a subject without a special manipulation by a user of a camera or a camera application of a terminal.
Generally, an auto-focusing scheme supported in a photographing device includes an infrared auto-focusing scheme, a contrast detection auto-focusing scheme, or a phase difference detection auto-focusing scheme. When a significant amount of reflection occurs, such as reflection from a plane of glass, or when a distance to a subject is far, the infrared auto-focusing scheme is difficult to execute for focusing. The contrast detection auto-focusing scheme executes focusing based on a contrast of a portion of a subject and thus, the contrast detection auto-focusing is difficult to execute when a contrast does not exist in the subject. The phase difference detection auto-focusing scheme generates two images using a lens in a detection sensor and executes focusing using an interval between the images. The phase difference detection auto-focusing scheme has difficulty in executing focusing when light, such as sunlight or a reflected light, enters through a lens or when a subject is significantly small. Therefore, there is a need for a method of effectively executing focusing when a portable terminal equipped with a camera photographs a picture and/or a video.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.